Campaigners have called for tougher controls on air guns after a schoolboy shot in the eye with an air rifle died from his injuries.

Mitchel Picken, 12, died on Saturday, two days after being hit in the right eye with an air gun pellet in Stockton Brook, Stoke-on-Trent.

He was taken to the University Hospital of North Staffordshire, where he was put in intensive care after having surgery.

Last night Mitchel's parents, Andrew and Joanne Picken, said they could not describe their grief at losing their "beautiful and intelligent" son. In a statement issued through Staffordshire police, Mr Picken, 37, and his wife, 35, spoke of Mitchel's closeness to his brother, Lewis, seven, and his passion for local football club Port Vale. "Mitchel was a beautiful, intelligent young boy, and we cannot describe our grief at losing him in such a tragic way," the statement said. "We have lost a kind and caring son."

Two 12-year-old boys detained by officers in the road in Stockton Brook where the schoolboy was shot have been released on bail until the end of this month pending further inquiries.

A postmortem examination found Mitchel had died as a result of a penetrating wound to the head.

Detective Inspector Neil Hulme, of Staffordshire police's major investigations department, said: "Our thoughts are very much with Mitchel's family and friends. This is obviously a very sensitive inquiry. We are working with the other two boys to establish exactly what happened, before deciding on the most appropriate way forward."

He said Mitchel's death was a "terrible reminder" of the dangers of children having access to air guns.

Gill Marshall-Andrews, of the Gun Control Network, called on the government to license air guns in line with other firearms.

She said: "There is still a culture in this country of air guns being regarded as boys' toys. It's very worrying because the message has not got through that air guns are not toys. They are lethal weapons when applied in certain circumstances."

The law restricts the possession of air guns to people over the age of 17. Children under that age must be supervised by an adult or at an approved club, shooting gallery or on private land.

Air guns can be bought online for £25, and there are no restrictions on who can sell them.

The Gun Trade Association estimates there are about seven million air guns in the UK in the hands of about three million people.

A spokesman said: "What has happened to this little boy is terribly sad. I don't know whether it was an accident or deliberate, but whoever owned the air rifle was committing a criminal offence by not securing it and ensuring that the boys were properly supervised. We believe that 99% of air gun owners and users are responsible people."

A spokeswoman for the Home Office said it did not record firearms offences by types of weapon, but the Gun Control Network believes half of more than 22,000 firearms offences in 2004-05 involved air guns.

In March last year Christopher Brain, from Leeds, was convicted of manslaughter after accidentally shooting dead his best friend Jonathan Hughes.

Last August Mark Bonini was convicted of the murder of two-year-old Andrew Morton, who died after being shot in the head with an air gun in Glasgow.

Gun law

· Air rifles and air pistols use compressed air to fire pellets or ball bearings. They are classed as lethal weapons but only the more powerful require a licence.

· Air gun owners must be over 17. Children under 14 in possession of an air gun must be supervised by an adult aged over 21. Those aged 14 to 17 can use a weapon unsupervised if they are at an approved club, shooting gallery or on private land.

· It is an offence for anybody to be in possession of an air weapon in a public place without good reason.

· The violent crime reduction bill would raise the legal age for possession to 18.